\" $NetBSD: perfused.8,v 1.13 2019/07/06 00:45:02 gutteridge Exp $

\" $NetBSD: perfused.8,v 1.13 2019/07/06 00:45:02 gutteridge Exp $
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\" Copyright (c) 2010 Emmanuel Dreyfus. All rights reserved.
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Dd January 29, 2012
Dt PERFUSED 8
Os
Sh NAME
Nm perfused
Nd PUFFS Enabled Relay to FUSE Daemon
Sh SYNOPSIS
Nm
Op Fl fs
Op Fl d Ar types
Op Fl i fd
Sh DESCRIPTION
Nm
is a userland daemon implementing the FUSE kernel level API.
It creates a
Pa /dev/fuse
socket for FUSE file system daemons to connect to.
Nm
takes care of mounting the file system using
Xr puffs 3 .
Pp
When the kernel sends a
Xr puffs 3
operation for the mounted file system,
Nm
will translate it into a FUSE request, and will send it to the file system
daemon through
Pa /dev/fuse .
The FUSE reply will be converted back into a
Xr puffs 3
reply and will be relayed to the kernel.
Pp
FUSE file system daemons must be modified so that they request
Nm
to perform the
Xr mount 2
system call instead of doing it on their own.
This is done by replacing
Xr mount 2
and the
Xr open 2
calls for
Pa /dev/fuse
with
Fn perfuse_mount
and
Fn perfuse_open ,
respectively, in their sources.
Xr libperfuse 3
must be used at link time.
Most FUSE file system daemons use
Nm libfuse
and will work unmodified, provided the modification is done in
Nm libfuse
itself.
Pp
The following options are available:
Bl -tag -width XdXtypesXX
It Fl d Ar types
Print additional debug information.
Ar types
is a comma-separated list of information types to print:
Bl -tag -width indent
It Ar puffs
Display PUFFS requests and replies.
It Ar fuse
Display FUSE requests and replies.
It Ar dump
Dump content of FUSE frames.
It Ar fh
Display file handle activity.
It Ar reclaim
Display reclaim activity.
It Ar readdir
Display readdir activity.
It Ar requeue
Display requeue activity.
It Ar sync
Display dirty flags and sync operations.
El
It Fl f
Do not fork, but stay in the foreground.
It Fl i Ar fd
Do not open
Pa /dev/fuse
but use the socket available from the file descriptor
Ar fd .
This is used when
Nm
is started from
Xr libperfuse 3 .
It Fl s
Enable debug output only when receiving
Li SIGINFO .
El
Sh ENVIRONMENT
See
Xr libperfuse 3
for environment variables affecting
Nm
behavior.
Sh SIGNALS
Bl -tag -width indent
It Dv SIGINFO
If the
Fl s
flag was used, toggle debug output.
Do nothing otherwise.
It Dv SIGUSR1
Toggle FUSE operation dump on and off.
When toggling off, the trace
is is stored in
Pa /var/run/perfuse-xxx.trace
(xxx is the filesystem mount point).
El
Sh ERRORS
The program logs to the syslog daemon as facility
Dq daemon .
For detailed debugging use the
Fl d
(debug) option.
Sh SEE ALSO
Xr mount 2 ,
Xr perfuse_mount 3 ,
Xr puffs 4
Sh AUTHORS
The program was written by
An Emmanuel Dreyfus
Aq [email protected] .
Sh BUGS
When
Nm
runs in the foreground (using the
Fl f
flag), some processes using the FUSE file system will
sometimes hang on
Sq uvn_fp2 .